Tag: QRP

After doing some portable operations with the KX3, I felt that having something smaller and lighter would allow my pack to get smaller and smaller. The only problem is that there is nothing smaller than the KX3 that is comparable unless you get a CW only rig. I decided to get the MTR (Mountain Topper Radio) that was developed by Steve Weber (KD1JV). It’s a 2.5-5W QRP CW rig that gives you the options for two bands.

The problem is that the MTR kits are produced and sold in small quantities with high demand. I’ve learned that Steve developed a version 2 of the MTR (3 bands) and had a pre-sale. Even though he gave out the wrong URL, people managed to figure out the correct URL and sold out within hours. I found out a tad too late and ended up having my money refunded.

I was a little bummed out. I was very excited that I might get this kit. I’ve never worked with surface mount devices and the CW only aspect of the rig would sort of force me to actually learn CW. After making my disappointment known, a local ham mentioned that he had an unbuilt kit from the orginal run that he might be willing to sell to me. Making fun of him didn’t help but I think the fact that I might learn CW might have compelled him to sell me his kit.

What did I just do?

Once I got my hands on the kit and took it home I inspected it (what ham doesn’t when they get a new toy?). That’s when I saw the components I’ll be dealing with. Very tiny resistors, capacitors and IC’s. The toroids were tiny and were not wounded. Everything is so… small. I have built ham radio related kits before but they were all through hole meaning that the parts like the resistors and IC’s had legs and pins the fit into the holes. They were large enough to where I can easily work with them.

I am not prepared for surface mount work. My soldering iron is this $10 Radio Shack 35W fixed iron. I knew it was not ideal for SMT as I have tried and failed using that iron. I need to learn how to solder surface mount and I need the proper gear to do it with. I’ve learned over the years that working with the correct tools makes the job much easier.

New Tools In The Shack

I’ve learned the hard way many times over that having the proper tools can make things a lot easier. I feel that I have everything needed for the job except for a soldering iron. I looking at the sub $40 Chinese type irons but I stopped myself from purchasing one. I wanted an iron that can last me for many years so I ended up purchasing a Hakko 888D soldering iron. At around $100 I felt that it was worth the purchase.

The Build. Day One!

Soon as I got the iron in, I went straight to work. Following the assembly guide I started with the IC’s and the MCU. I felt that you are starting with the hardest part of the job by soldering small SMT IC chips with small leads and small gaps. I avoided installing the MCU and DDS chips until the other ICs were installed. Once all the IC’s were installed, I used a jewelers loop and checked my connections. The MCU was crooked a bit and thought it was still good so I kept chugging along. I installed the resistors on the bottom of the board and called it a night.

My working area. You’ll see the board with solder, tweezers, assembly manual, solder, 10X Jewelers loop, desk lamp with magnifying glass and my new soldering iron. When I purchased the soldering iron, I also purchased different sized and shaped tips.

The Build. Day Two

Next day I got back from work and installed everything else. It wasn’t really bad as I thought. The soldering Iron was tight in some places but it appeared everything went quite well.

Here is a close up of my soldering. It could be better but I would say not too bad considering I’ve never done SMT work before.

Power On Time.

I didn’t want to wire up the power, headphones or anything else because I was going to design a case but in order to make sure it worked. I needed to wire it up. Soon as I hooked up the battery… Nothing! It did’t lite up, It didn’t beep. The only thing I notice was a slight noise in the headphones. Sounded like the noise of when you turn something on.

What Went Wrong?

As panic starts to set in, I was worried that I now have a nice new expensive brick on my hands. All that time, energy and money spent on the kit and tools needed seemed be wasted. Out came the jewelers loop and soldering iron. I double checked every connection. Then I took out the multimeter and followed the troubleshooting guide in the manual and started checking voltages coming out of the regulators. Everything was checking out. The only thing I see is that the MCU was a little bit crooked.

I tried re-soldering the MCU but it proved to be very difficult. I used solder wick and suction tools that did not help, the chip would not move for me. For me the only choice was to remove the MCU. But how? After some internet searching I decided to use enameled wire and snake it under the chip where the leads meet the chip. I then touched the soldering iron to the leads and slowly pulled the chip off.

Using that method allowed to me to remove the chip, but in the process I damaged the MCU. The above images is not representative of my soldering work. It was more of a panic move and I just wanted to get the chip off without damaging the pads or board. The pads were in great shape and I’m just lucky nothing else happened.

Dealing With Steve Weber

Well it’s obvious the chip will need to be replaced. There are two options available. Beg steve for a new chip or purchase the MCU and flash it using a MSP Launchpad. I almost went the latter because Steve just released V2 and I am sure he was busy dealing with that and life in general but I decided to e-mail him anyways.

Dealing with Steve was a pleasure. I know these radios is not his full time job but he replied within a reasonable time and he was willing to send out a pre-programmed chip for my version of the MTR. Since I was having him sending me stuff, I purchased a case because the price he was asking was more than fair.

Attempt #2

Now that I have the new MCU, I promptly installed it. This time I quadruple check to make sure the chip was aligned properly before soldering. It went much better.

When I applied power I jumped for Joy as I saw the LED come to life and the sounds of CW in my headphone. I did some initial testing and then installed the last toroid.

It’s… ALIVE!!! ALIVE!!!

Now that it turns on, it’s time to make the adjustments needed for proper operation. Thankfully I have Acquired the test gear I needed over the years from mostly local hams looking to clean their shack. I have a decent frequency counter, oscilloscope and a station monitor.

The manual found on the Yahoo Groups page provided step by step installation and tuning. It made things a lot easier.

First thing I did was adjusted the reference oscillator frequency to match exactly 10MHz. This was very easy. Just pushing a button until I see 10Mhz on the counter. There are reference points on the board to where you can easily measure things.

Adjusting the LO to find the center of the passband. This was a little tricky because I didn’t fully understand the manual and process. In the tuning mode the MCU sends out a tone and I adjusted it by watching the signal peaking on my scope while counting the steps between the peaks. I then went backwards only half of the steps. Hopefully it was done correctly. For me, this was the hardest part of tuning.

Here I am adjusting the receivers filters. With the station monitor I injected a signal into the MTR through the antenna port and adjust the band capacitors until the signal was at it’s loudest. I did the same thing on the other band. This was quite easy.

Last thing I did was hooked it up to a dummy load and checked for output wattage. Using a variable power supply and a DMM hooked in-line, I’ve sent out a tuning signal and adjusted the power supply until the DMM read 9Vdc with a TX load. I was seeing approx 2.5W which is within spec.

Time to get one the air

Now that it’s built and tested, It’s time to get on the air and see what I can (not) do.

Heh, it’s smaller than my paddle. What’s great about CW is that you don’t have to call CQ over and over again hoping someone would come back to give you a signal report. Just call CQ a couple times and head over to the Reverse Beacon Network where you can see almost in real time where your signal is being heard. There are receivers all over the world scanning the bands for signals.

Here are my results using just a crappy 9V battery. I am pleased to see that not only are stations hearing my signal, but they are on the frequencies that the MTR is tuned to. While I was testing the worst thing happened… Someone replied. I tried very much to work the person. I know the call was a K2 something but that’s all I could make out.

Final Thoughts

This was my first actual kit that I built, It’s also the first time that I ever worked with tiny surface mount devices and even though I messed up the MCU, it was really fun to build. Soldering SMD seems to be a nightmare but after the first couple of parts, it felt real easy and it felt that I was working much quicker compared to through hole parts. This project is also a big kick in the ass to learn CW because I want to use this rig. I’m all about packing very lite when it comes to SOTA and even though I love the KX3, I feel it would be more of an adventure using the MTR. We’ll see.

I had some time to myself on Saturday (6/14) which is rare so I decided to play a little radio on top of a mountain/hill. I found that when it comes to doing SOTA that ends up being a last minute effort to get my stuff ready. This time I wanted to do a summit that I have never done before. I decided to go to Peaked Mountain located in Hampden/Monson MA. I notified SOTAwatch and local SOTA/Ham facebook groups that I will be out. I find that letting many people know that you’re going to be activating will increase your chances of a successful activation.

The Hike

Expecting the unknown for both the hike and summit I over packed which is better than not packing that one item you’ll end up needing. The mountain is closer to my QTH then I originally thought which was great. The hike also wasn’t bad. The trails were (now) clearly marked and was able to make it to the summit in 20min or so. My only concern was the rain.

Welded Sign/Box near the summit

The Setup

Due to the overcast I didn’t have much time to really enjoy the view. I wanted to get on the air as fast as possible in case it was going to rain. However I have a new G5RV jr that I home brewed to replace the crappy G5RV that I was using. I also took along the vertical end fed (EARCHI) as I’ve never used it for SOTA. I wanted to put both up.

Here you can see the G5RV mounted to the Jack Kite 31′ fiberglass pole. I used an eyebolt that is connected to the center insulator and slid it down the mast. I might place some tape at that spot to keep the eyebolt from wearing out the fiberglass tube. Also pictured is the end fed that is attached to the tip of the pole.

Another photo showing my mini G5RV. I made custom insulators using plexiglass that doubles as winders

Here is a photo showing my old G5RV next to my new one.

Here is a shot of the antenna with both antennas attached.
Setup took less than 10Min with most of my time spent untangling wires.

Getting On The Air

After sending out a spot to SOTAwatch and my local SOTA group I was on the air. However no one is coming back. Usually I get people within minutes coming back to my crys of CQ. After about 10min or so, Jim (KK1W) came back to my crys and made my first contact. Other people started to trickle in. After AJ5C and N4LA I heard a couple DX contacts from Romania and England but was un-able to establish contact

My setup with the KX3, Wouxun for VHF and my 9:1 match for the endfed

I tried switching around bands and antennas to make my contacts. I knew I could make contact with KB1RJC and KB1RJD if I went onto 40M and sure enough they were on and waiting (thank you). They made my 4th and 5th contact.

My Seat with Antenna in the background

After making a couple more local contacts, I called it a day. I have 7 contacts so I can consider the summit to be officially activated. The sun started to come out and the skys started to clear up a bit and was able to enjoy the view from the mountain top

Views from the top of Peaked Mountain.

Overall Experiences

I’d say this was the hardest HF activation I’ve done to date. It was not the hike because that was very nice and easy. It was hard because I am not sure if it was my antennas, location, band conditions or a combination of all three that was making it difficult for communicating. There were also many hikers up on the mountain and I ended having to explain “what that is” many times over which took me away from the radio. Even though I love explaining what my setup is to non-hams, I just wasn’t in the mood but I didn’t want to come off as rude. I love the location and mountain and this location is now on my list of summits to activate next year.

In the search for the “Wonder Antenna” that is small, portable and easy to setup, I’ve decided to build an Endfed antenna using a 9:1 match. This antenna has been made popular by the Emergency Amateur Radio Club of Hawaii (EARCHI). It consists of 30ft of wire fed into a 9:1 UnUn (Unbalanced to Unbalanced).

I’ve been wanting to make the antenna for quite a while but I’m lazy when it comes to ordering things online. During the spring of 2013 I went to a regional hamfest located in New Hampshire hoping to find the T106-2 toroid that was called out for in the plans. I saw a bunch of red toroids and decided to purchase them hoping it was the correct mix and size.

I ended up with what appears to be a T130-2 toroid. It’s a little bit bigger than the T1o6 but uses the same mix.The Build

It wasn’t that bad… If you follow the instructions the build only takes about 15 minutes or so. I mounted everything inside of a plastic tooling container. Instead of using a chassis mount SO-239 I went with a small length of RG-58 coax with a BNC at one end. The reason I did that was because there is always a strong chance that I’ll forget the coax and could at least use the pig tail connected to the radio.

The plan is to get this into even a smaller container.

Let’s hook it up to the Analyzer.

Before attaching it to my radio, I wanted to hook it up to the analyzer just to make sure I have the correct toroid being used. When it comes to buying toroids at hamfests, you could be taking a gamble unless it’s clearly marked. I might have purchased a different type even though it’s red in color.

What I’ve done is hooked up a bunch of resistors to the output and ground of the unit. The resistors should add up to 450ohms. Since it’s a 9:1 balun (or unun in the end use), 9 goes into 450 50 times which we should see 50ohms on the otherside if all is correct.

With the 450 ohm load. The analyzer is see approximately 50ohms across the HF bands allocated for Amateur Radio. However on 6M the SWR and impedance is quite high. However this is most ideal situation. That’s not going to happen when the wire is hooked up as it will not have a 450ohm resistance.

Here is a video I made testing the EARCHI with the MiniVNA PRO

What about the counterpoise or the other half of the antenna?

If you look at the design, you will see that the “ground” is hooked up to the shield of the coax, so it would be suggested that you run some length of coax between the match box and your radio.

Testing the antenna in the real world

One could sit there and talk all day about using the antenna. Let’s see what it can do

I tested this right outside on my deck using a 31 foot fiberglass pole. The wire is 30ft of #18 Poly-stealth.
The antenna only took around a minute or two to raise. I wasn’t really planning on making a video or even using the antenna that day so the batteries on the KX3 were not charged nor did I have it hooked up to an external source. I was using 3watts to conserve battery.

I went onto 15m and within minutes I managed to make a DX contact with LY10NATO which is a special event station in Lithuania. Not bad considering my conditions. The bands must have been in good shape. I then went to 20 and made contact with W1AW/4, an ARRL Centennial station in Tennessee.

I know it’s not proper to judge an antenna based solely on contacts but it just proves that it works. If you need a QRP antenna that is portable and can get you on the air quickly then I would suggest the EARCHI to anyone. It’s easy to build and if you don’t have the time you can purchase one from EARCHI. It’s not a “Wonder Antenna” by any means but it’s hard to beat consider the cost and ease of use. Also having a decent match (tuner) helps.

Edit (4/3/2014): Someone on Youtube asked about SWR reading with the EARCHI. I decided to hook up the antenna to the KX3 with the internal ATU option using a couple configurations and here are the results. Please keep in mind the ATU in the KX3 has a wide ratio and could match a lot of wire. Doesn’t make the antenna any more efficient but it makes it work.

KX3 With KXAT3, EARCHI Antenna with around 30ft of #18 Poly Stealth and around 20ft’ RG 58 coax

Band

Ratio

160m

18:1

75M

1.1:1

40M

1.0:1

20M

1.1:1

17m

1.1:1

15m

1.1:1

12m

1.2:1

10m

1.0:1

6m

1.0:1

KX3 With KXAT3, EARCHI Antenna with around 30ft of #18 Poly Stealth and around 1ft’ RG 58 coax

Band

Ratio

160m

17:1

75M

4:1

40M

3:1

20M

1.1:1

17m

1.0:1

15m

1.0:1

12m

1.0:1

10m

1.0:1

6m

1.1:1

You’ll see that adding a length of Coax will help you out in the lower frequencies. Please note that results will vary depending on your equipment.

Let’s hook up the analyzer using the EARCHI w/ approx 30ft of #18 wire and approx 20ft of RG58 Coax

Since it was a warm weekend than normal, I decided to take advantage of it and hike up Bare Mountain in Granby/Amherst area in Massachusetts and do a SOTA Activation.

Elecraft KX3 Ready to go with Spare Batteries

Since this was a spur of moment thought, I didn’t have time to properly prepare my equipment. However usually when I come home from an activation, I take the time to repack my bag and make sure all the basics are included because I know I’ll be grabbing it with short notice. I could consider it my “Go-Kit” as it’s an entire HF station with antenna that fits into a small backpack.

Need More Batteries

For this trip I didn’t even charge the battery from the last activation. Since I’m using a 3 cell (3S) 2200mAh RC/ battery with each cell being 3.7v, The battery pack will be fully charged at around 11.1v to around 12.6v. The KX3 Folds back TX power from 10w to 5W when the voltage dips below 11. This does not give me much room to play with. I am able to do an activation at 10W without much issue. If the TX power folds back, it’s usually at the end of my activation so my last contacts would be at true QRP levels. I could purchase a LiPo or LiFePo4 battery that has the proper voltage but that could end up costing me quite a bit of money compared to the cheaper RC batteries used in Quadcoptors and similar. The other option is purchase a 4 cell battery which could gives a 14.8 to 16.8v. It’s a little too much for the KX3 but you could step down the voltage using a couple diodes inline until the voltage drops below a certain point. The downside to that is the diodes will heat up. I’ll stick with the 3 cell for now but I should buy more and alternate them. At $10 a battery, you really can’t complain.

Before the Hike

Even though it’s short notice, there is some preparation that is needed before you leave. Besides making sure you have everything and double checking, it’s strongly suggested that you submit an activation notice (alert) to SOTAwatch.org. Even more so if you’re a CW operator. That way people will expect you. You wouldn’t want to spend all this time hiking and setting up gear to make zero contacts. Since SOTA is gaining more popularity, it means there are more chasers and activators participating. There will always be someone listening out for you as long as you tell them when and where you’ll be. Cell/Data service at the summit is a huge advantage as you’re allowed to Self spot on the SOTA Cluster. CW ops have it even easier because if you send an alert through SOTAWatch, when you start calling CQ the skimmers will pickup your signal and automatically spot you on the SOTA Cluster. That’s pretty darn neat. I know people that have been involved with SOTA for a long time and they’ve told me stories of how they failed to make the minimum of 4 contacts. I have yet to have one of those activations and I hope it never will happen.

The Hike

The hike up wasn’t bad and the use of crampons helped since there were icy spots in the snow. After some huffing and puffing I made it to the summit with some time to spare.However all the time was used tring to untangle my mess of the mini G5RV that I use. It wasn’t designed for portable use and it uses #14 THHN wire. I took along tent stakes but ended up tying off the ends to near-by trees because the ground was frozen. I “Secured” the mast using bungie cord to a tree branch. It held up quite well

Mini G5RV in a inverted V configuration. Mounted to a Jackite pole

Once everything was setup and checked, Out came the logbook and sent a spot over SOTAWatch.org. It didn’t take long for the traffic to come. There were times where I had pileups to work me which is real fun.

Operating conditions. Notice the lack of seat.

The following operators worked me from the summit, if you worked me and you either see your callsign wrong or not there, please contact me. I had a real hard time trying to write down calls correctly and It’s possible that I messed up your call. I try to check each contact against QRZ.com’s DB. It’s even better when the profile mentions SOTA as it makes me feel better the call is correct.

(20 METERS – Start 16:34Z)

N4EX

W0MNA

K1MAZ (SOTA Jerks)

G4OBK

W7RV

W5ODS

KU4GC

K5WI

KD8NBB

DJ5AV

AA7DK

NS7P

WA2USA/4 (In Florida)

N7AMA

KB9VZU

EA7HX

G4UXH

G0VWP

G0RQL

G6TUH

K8SSS

KK1W (SOTA Jerk)

KAEZE

AK4BH/QRP

KC9TTR

W5RST

(12 Meters – Start 16:55)

W5RST

AD5A

KK1W

W0KEU

(15 Meters – Start 17:03)

G6TUH

M0MDA

EA2DT

M6ARE ??

G4UXH

(40 Meters – Start 17:13)

KB1RJC

KB1RJD

VE3JCW

N2ICE ??

N7UN

KK1W

(10 Meters – Start 17:30)

W7RV

G6TUH

(Contacts with other SOTA Summits)

W7IMC (W7I/SR-138 Idaho)

KI4SVM (W4C/WM-039) (NC QSO Party)

Over 45 contacts were made, I also chased some DX I heard while scanning around the bands and chasing other SOTA activations. I’m glad to make a couple Summit to Summit contacts which to me is more thrilling as we’re both on summits with less than ideal operating conditions.

There were a lot of other hikers up at the summit and some came over to talk and were amazed that I was contacting Spain and England considering what I had.

View from the other side of the Summit. You can see UMASS, Amherst and Hampshire college from this view

I could have stayed longer but Kneeling in the snow wasn’t helping me out. I need to find an easier way to be more comfortable during the winter activations. Thinking about using a kneeboard that I can attach my radio to that also has a clock. The hike down was a lot harder than the hike up. I kept sliding and had to use my antenna mast as a walking stick at times.

Notice someone made little snowmen along the trail

Lessons Learned

Besides having extra batteries, I think some kind of seat or something that would allow me operate more comfortable. I was either standing or kneeling down in the snow which was more damaging to me than the hike. It was extremely difficult to log contacts while holding the microphone.